1. Field of the Invention
The present invention relates to a glass substrate laser cutting device and a glass substrate breakage detecting method, and more particularly, relates to a glass substrate laser cutting device with a real-time breakage detecting function capable of monitoring breakage of a glass substrate in real-time during a glass substrate cutting process by organically using a vacuum suction pressure and a laser cutter for cutting the glass substrate.
2. Description of the Related Art
In a process of cutting a glass substrate using a laser beam, it is very important to maintain flatness of a glass substrate which is a workpiece due to the nature of the process. Accordingly, the glass substrate generally cut by a laser is placed on a table which is highly precisely processed so as to have high flatness. As the material of the working table, metal, marble, or the like is widely used, and a sheet or a pad formed of a soft material is attached onto the working table so as to prevent damage of the surface of the glass substrate. However, since the sheet or the pad is formed of a combustible material, soot may be generated during combustion when the surface is irradiated with the laser beam, so that the optical system and the optical path are contaminated, which causes critical damage in the laser cutting device. Accordingly, since the combustible material of the sheet or the pad is exposed to a section in which the glass substrate is damaged, it is essential and important to determine whether the glass substrate as the workpiece is abnormal prior to the laser cutting.
As disclosed in Korean Patent No. 0510720, the existing glass substrate breakage detecting method is generally configured such that optical sensors are installed and fixed to both side surfaces of a glass substrate based on a glass substrate conveying direction and breakage of both side surfaces is detected when conveying the glass substrate.
In the above-described case, since the laser cutting direction is aligned with the glass substrate conveying direction, the optical sensors positioned at the lower or upper portions of both sides of the glass substrate may inspect the breakage state of both sides to be cut by a laser while the glass substrate is conveyed without a separate carriage.
Accordingly, in order to cut the other both side surfaces of the square glass substrate by a laser, there is a need to check whether the other both side surfaces are abnormal in the same manner as above. For this check, a device for changing the direction of the glass substrate needs to be provided. As a result, it is possible to determine whether all sides of the glass substrate are abnormal through all the above-described procedures.
However, in many cases, there is a limitation in that the damage of the laser optical system and the optical path caused by the damage of the glass substrate may not be basically prevented only by the existing glass substrate breakage detecting method.
That is, even when the glass substrate state of both sides to be cut by a laser is normal based on a time point at which the glass substrate is conveyed, if the breakage portions of the other both sides which are not detected upon aligning the glass substrate for the laser cutting process increase in size and the combustible material below the glass substrate is exposed, there is a problem in that soot generated during the laser cutting contaminates the optical system and the optical path.